Hey folks as the title says 1986 5.7 GM OMC Upper Gear box is frozen. I assume we didnt refill the lower unit properly and caused it to freeze up on the lake. We where going across the lake and it stopped suddenly. Couldn't been 10 mins. I have found after pulling the terndrive off, the teeth on the drive shaft are twisted from the sudden stop and you can not turn the shaft on the gearbox. Out of gear the prop will spin still. I'm thinking the grease was not placed in properly which caused it to lock up from lack of grease on the upper half. Whats my best course of action to repair this thing? We open the top half of the gear box and nothing appears to be broken there of course not sure about the bearing. We tried using a wrench to spin the shaft on the inside but won't budge. Any idea what I'm looking at far as parts or is it better to get a new gear box? I know I need a new shaft since its twisted and might as well replace the U-joints since its off. Is it likely a bearing or something more internal in the lower half of the box? Any good sites that have a break down of the unit or a place for parts that shipping wont cost the crude out of me. We live in DFW, Tx.
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